The ancient period is one of the most difficult for the reconstruction of the historical-geographical evolution of the North-Western Black Sea region. The most important source of information on the region is the “Geography” of Claudius Ptolemy (middle of the 2nd century) – the pinnacle of ancient historical geography and cartography, including detailed descriptions of the location of geographical objects. The localization of the toponyms is an object of great interest both for historians and for archaeologists, and in relation to the North-Western Black Sea region it is a great interdisciplinary scientific task. The research within the framework of the historical-geographical approach bases on the complex of classical and modern methods. It demonstrated that when comparing archaeological and architectural objects preserved from ancient times with modern, as well as the geographical names marked on ancient maps, it is possible to localize a number of cities mentioned by Ptolemy in the middle part of the course of the Dniester reasonably.